How to force a Kendo UI modal window to center in a page? and how to disable all the actions?

Have you tried hiding it, then centering and opening it?

var accessWindow = $("#accessDiv").kendoWindow({
 actions: {}, /*from Vlad's answer*/
 draggable: true,
 height: "300px",
 modal: true,
 resizable: false,
 title: "Access",
 width: "500px",
 visible: false /*don't show it yet*/
}).data("kendoWindow").center().open();

from: http://www.kendoui.com/forums/ui/window/kendowindow-center-doesn-t-work-when-inside-an-iframe.aspx